Method for the treatment of animal fibers



Patented Jan. 25, 1927.

MAX BERGMANN, EUGEN IMMENDtiRFER, AND HERMANN LOEWE, 0F DRESDEN, GERMANY.

METHOD FOR THE TREATMENT OF ANIMAL FIBERS.

No Drawing. Application filed June 7, 1924 Serial No.

When treating animal fibers with strongly acid agents a more or less considerable damaging of the mechanical properties of the fiber frequently occurs.

Now we have found that this damaging of the animal fiber by strongly acid agents can be avoided and that even an improvement of the mechanical properties of the fiber can be obtained if the animal fibers or the material and products consisting thereof or prepared therefrom, as for instance woolen textiles, silks or silk tissues and so on, are treated either before or during the action of the strongly acid agents with the waste liquor resulting from the manufacture of cellulose from wood by means of sulphurous acid and the like (hereinafter called waste sulphite liquor) or the active constituents of this waste sulphite liquor. Instead of the common waste sulphite liquor also such waste liquor of this kind may be employed which has previously been changed by chemical means, or also chemically converted constituents of the waste sulphite liquor may be used, said changing of the waste sulphite liquor or its active constituents for instance being obtained by the action of oxidizing means.

The method may be employed in all those cases where the animal fiber has to be treated with strongly acid means, as for instance in the carbonizing of common wool or of the so-called artificial or shoddy wool. Though the damaging of the wool by acid means, e. g. in the carbonizing process, cannot be stated exactly till now. nevertheless wool (e. g. shoddy-wool) which has been treated in such a, manner will only have a short life time and therefore can only be cn'iployed for the manufacture of tissues of inferior valuc. \Vithout doubt the short life time of the so-called artificial or shoddy-wool at least in part is a consequence of the damaging influence of the acid in the carbonizing process. Now the present invention shows a way not only for preventing such a damaging effect but also for allowing to treat the fiber if desired. with stronger acids than usual and than was possible till now.

In this method either raw or purified waste sulphite'liquor or its active constitucuts or their products of conversion may be 718,626. and in Germany February 23, 1923;

employed either separately or in mixture with one another or with other substances.

The invention will be hereinafter eX- plained by a number of examples.

Example Z. grams of washed, spun wool free of fats are drenched with sulphuric acid of 5% under the conditions usual in the so-called carbonizing process; then the wool is wrung and dried at 90 C. The thus treated wool shows a damaging (though not very high) of its mechanical properties especially of its resistance against tearing. if compared with uncarbonized wool. If however waste sulphite liquor is added to the carbonizing bath in a quantity corresponding only to about one fifth part of the contents of pure sulphuric acid, i. e. 1% of the, sulphuric acid employed, a remarkable increase of the resistance against tearing is obtained.

Example 2.If two hundred times the quantity of sulphuriq acid of 20%. is employed instead of that indicated in Example 1, and said quantity of acid is allowed to act on the wool during 30 minutes at a temperature of 95 0., the resistance against tearing will diminish to one third of its original value when no protective means are employed. But by the addition of waste sulphite liquor (in a quantity of 3% of the whole liquid) to the acid bath the resistance against tearing will only be diminished to one half of the original value.

Example 3.VVhen treating wool with acids, waste sulphite liquor is added which has previously been treated with ozonized air, said treated waste sulphite liquor being employed in such a quantity that the acid liquid will contain one or a few per cent of the concentrated waste sulphite liquor. The resistance of the wool against tearing thereby preserves its original value, whereas it will be strongly reduced if no waste sulp iite liquor at all is employed and it will not be just so high if untreated waste sulphite liquor is used.

Envwnple 4. 1 kilo of concentrated waste sulphite liquor is heated to a temperature of to C. with 240 grams of potash chlorate and 200 cubic centimeters of concentrated hydrochloric acid. The mixture will foam up strongly in the beginning of the reaction. The mass is further heated during two hours, then cooled and neutralized by means of soda solution. The thus obtained product may directly be employed as protecting means. Also in this case the resistance of the Wool etc. against tearing will not be damaged by its treatment with strongly acid agents, such as sulphuric acid. The effect of a Waste sulphite liquor treated and converted in the indicated manner is yet a better one than that obtained by the employment of the untreated, usual Waste sulphite liquor.

Having now particularly described and ascertained the nature of our said invention we declare that What We claim is:

1. A method for the protection of animal fibers during the separation from vegetable (ibers by earbonization rith strongly acid agents, consisting in performing the carbonization While treating the material with active constituents of Waste sulphite liquor.

2. A method for the protection of animal fibers during the separation from vegetable fibers by carbonization With strongly acid agents, consisting in performing the carboni- Zation While treating the material with waste sulphite liquor.

In testimony whereof We have hereunto set our hands.

PROF. DR. MAX BERGMANN. 

